This invention relates to brakes for vehicle wheels, such as road, rail and aircraft vehicles, such as a partially lined disk brake conventionally including a rotating brake part (brake disk) and a stationary brake part (brake shoe) which are brought into cooperative braking interaction by a hydraulically operated piston.
In virtually any specific vehicle field, but particularly in the automotive vehicle field, brakes must have high reliability, power and service life coupled with relatively small size to accommodate reduced mounting spaces of today's road vehicles. Such brakes must meet or exceed strict vehicle weight limitations, particularly those set for automotive vehicles and railroad vehicles. Such factors, together with the need of using ecologically harmless materials (asbestos-free friction material) are at the point of reaching economically justifiable limits.
Above all, the high price of asbestos substitutes and the working stresses of the friction linings when considered in connection with the admitted high driving speed of motor vehicles of the present generation requires excellent brakes and particularly brake linings which will fit properly, will wear evenly, will stop vehicles quickly, and can achieve low initial cost as well as low cost for subsequent maintenance and/or repair.
Problems such as those outlined earlier are now very difficult to master through redesigning conventional brake systems or modifying the brake linings thereof. However, it is necessary to maintain low weight of the brakes without increasing the constructional dimensions or reducing the friction load surface or the thermal stress of the brake lining friction material. In simple terms, if the brake lining friction material can achieve excellent braking with corresponding reduced wear, considerable savings of cost will result from the standpoint of maintenance and repair.